Relative shutter noise. Some claim the 20D is overly loud, I wanted to see how it compares to other 35mm format cameras.

The setup involved a unidirectional Hiel microphone mounted in foam, the front of the mic was positioned along the centerline of the lens, and at a distance of 7 inches from the focal plane of the camera under test.

A sound card was used to sample the mic output and display the relative amplitudes on screen.

The cameras sampled were all Canon, the FTb, the EOS-3, the Elan 7e, the New F-1, the 1D, the D60 and the 20D.